Algal blooms in Lake Erie are a reality. Though not as bad as those seen in the 1960s
and 1970s, algal blooms (both harmful and non-harmful) occur on an annual basis
in Lake Erie. The National Atmospheric
and Oceanic Administration (NOAA), in junction with Heidelberg University’s
National Center for Water Quality Research, has developed a new monitoring
program to predict the severity of algal blooms based on the combination of
current measurements of phosphorus loading from the Maumee River for the season
to date with historical records from past years. According to NOAA, “The severity of the
western Lake Erie cyanobacterial harmful algal bloom (HAB) is dependent on
phosphorus inputs from March 1st through July 31st, henceforth the loading
season. Based on 12 weeks of data (March
1- May 23, 2015), the extensive severe blooms observed in 2011 and 2013 are not
projected to occur this year.” The
positive outlook for Lake Erie this year is due to a relatively dry spring
which resulted in less discharge and lower phosphorus loads into the western
basin. Yet, NOAA stresses that there is
some uncertainty in their projection because the loading season still has 2
months to go. Updated forecasts for the
algal blooms will be released by NOAA periodically.
In addition to the potentially harmful algal blooms,
those wishing to enjoy Lake Erie’s beaches should be mindful of bacteria levels. The Erie County Health Department monitors
water quality near 25 beaches in the county four times per week from Memorial
Day to Labor Day. According to their
Erie County Health Department’s website, “Our employees strive to ensure that
unsafe swimming conditions are communicated to Erie County residents as quickly
as possible and in doing so reduce the risk of unwanted illness in the swimming
public. Our Sanitarians collect and
analyze samples for the presence of E. Coli bacteria, which is a good indicator
of bathing water contamination and if present increase the risk of disease
transmission to swimmers.” The health
department findings have a one-day delay from time of sampling to
reporting. These results are reported in
local newspapers, announced on local radio stations, and are available on their
website (www.eriecohealthohio.org/environmentalhealth.html).
The results provided by the Erie County Health Department
are a valuable means of alerting beachgoers of potentially harmful bacteria. The methods employed by the Health Department
involve collecting water samples from their 25 selected areas, transporting the
sample to a laboratory, and determining the numbers of E. coli in the sample. Unfortunately, there is a delay in the
reporting because it takes at least 18 hours to grow E. coli in the laboratory.
Hence, by the time these results are
available, water-quality conditions may have already changed. In an effort to provide real-time forecasting
of E. coli levels, a system called Nowcast has been created as a result of multi-year
partnerships on several projects between the U.S. Geological Survey (USGS) Ohio
Water Science Center (OWSC), and other federal, state, and local agencies and
universities. Nowcast uses predictive
models based on easily obtained measurements such as rainfall and wave height
to estimate levels of E. coli and to calculate the probability that the
bathing-water standard will be exceeded.
The calculation and reporting of these results takes less than an hour. Nowcast has been in use since 2006 for
Hunting Beach in Bay Village. Other
beaches have been added to the monitoring program since then. Ohio is currently monitoring nine sites
including Nickel Plate Beach in Huron and Main Street Beach in Vermilion. Nowcast results are updated by the Erie County Health Department by noon on
Monday through Thursday during the swimming season and can be found on the
Nowcast web site (www.ohionowcast.info/index.asp).
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